Stop mechanism for knitting machines



Dec.v 8, 1931. J. WACHSMAN 19 3 y STOP MECHANISM FOR KNITTING MACHINES Filed Nov. 5, 1930 w 3 M 5% 55 v 1' 155 50 15 if f 'miq. E

llllfilll E if? ATTORNEY Patented Dec. 8, 1931 UNITED STAT S PATENT OFFICE JACOB WAGHSIAN, OF BROOKLYN, NEW YORK STOP MECHANISM FOR KNITTING MACHINES REISSUED v Application filed November 3, 1930. Serial No. 498,179.

My invention relates to electric stop mechanisms of the general type disclosed in m application filed January 15, 1929, Serial N 0. 332,644, and in my Patent No. 1,778,097, issued October 14, 1930. i I

Primarily the invention has for its object to improve the mechanisms disclosed in my previous application and patent in order to render the operation of the device more positive and in order to reduce friction on the thread toa minimum, and thereby reduce the danger of fraying the thread and possibly causing it to break. I

Again, it is an object to provide a gravity actuated lever which will tend to lift the thread off the surface of the spring-held lever arms, thereby to reduce the area of contact between the thread and these parts, instead of having the gravity actuated lever press the thread down on the surface of the spring-held lever arms as in my previous application and patent. 1 I

Further, it is an (ibject to provide against the accidental closing of the circuit by a mere slacking of the thread.

Other objects will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and ends, the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will be first fully described in the following detailed description, then be particularly ointed out in the appended claims, reference Being had to the accompanying drawings, in

which p Figure 1 is a side elevation of the embodiment of my invention which has been especially designed for use with fine thread, the

signed for use with medium weight thread.

Figure 6 is a perspective view of a further electric circuit of the stop motion mechanism may be regulated.

embodiment which has been especially designed for use with a heavy thread.

In the drawings in which like numerals of reference indicate like parts in all of the figures, I provide a housing consisting of a supporting plate 1 having a bent over end 2 for mounting and provided with shoulders 3 to constitute stops for limiting the movement of the spring-held lever 13 hereinafter again referred to. The plate 1 is also provided with 00 a cut-away portion 4 while the bent over or mounting portion 2 of the plate is provided with a hole 5 for the reception of a screw or bolt 6 by means of which the device ma be mounted on a suitable supporting part of the knitting machine. The housing also includes a box 7 whose front is closed by the plate 1 and which is secured to that plate by screws or bolts 8. Mounted within the box 7 is a long contact 7 spring .9 and a short contact s ring 10 secured to a suitable terminal be t 11 that is mounted on, but insulated from, the box 7.

Bearing notches 12 are provided in the sidewalls of the box 7 for the spring-held lever 13 whose parallel arms embrace the plate 1 and extend forwardly thereof, terminating in porcelain fingers 14 having concave portions 15 to hold the thread T. The spring-held lever where it passes through so the box 7 is provided with a heel 16 for effecting contact with the s rings 10 and 9 when the lever 13 is ulled' own against the tension of the holdack spring 18 as will later be explained. The spring 18 has one end hooked into a stirrup 17 that is carried b the heel 16 and it has its other end ancli ored to a screw 19 which carries an adjusting nut 19a whereby the tension of the spring 20 designates a gravity actuated lever,

4 which is mounted in suitable bearing notches 22 in the side walls of the box 7 and which has a loop portion or heel 21 to engage the contact spring 9 when the lever 20 1s raised beyond a certain limit as will later be more full explained.

T e lever 20 has a rearwardly extending portion 23 bent over to underlie a pivoted weight-lever 24 which is also mounted in suit- 1 0 able bearing notches 25 in the side walls of the box 7 and which has for its purpose to over-balance the lever '20 and continuously tend to elevate it to a position higher than that indicated in dotted lines in Figure 1, whereby when so elevated to the highest position the heel 21 of the lever 20 will engage the contact spring 9 and close the electric circuit.

The lever 20 in the first embodiment of my invention has its front end bent into approximately the shape of the letter M thus providing two loops 26 with three parallel rods 27 which lie between the porcelain fingers 14 of the spring-held lever 13 when the thread T is in position, see Figure 1.

28 is the downwardly and forwardly inclined portion of a guard member formed of wire and secured at 6 to the bent over end 2 of the plate 1, the guard member also including rearwardly extending approximately horizontal portions 29 which merge with vertical back stop portions 30, from one of which there is an upwardly and rearwardly extending portion 31 that is anchored at 8 to the plate 1, see Figures 1, 2 and 3. The construction of the guard is such that when the gravity actuated lever 20 is free to rise the portions 29-28 of the guard will pass within the loops 26 between the parallel portions 27, it being understood that the vertical portions 30 continuously lie projected through the loops 26 and between the fingers 14, see Figures 1 and 2.

The portion 31 of the guard which is anchored at 8 is continued laterally as an extension 32 to constitute a stop for limiting the upward movement of the gravity actuated lever 20. By bending the projection 32 up or down (see Figure 2) the height to which the lever 20 may be permitted to rise before engagingthe stop 32 may be correspondingly'varied.

In the embodiment of my invention shown in Figure 6, thoseparts which are of the same construction as shown in Figure 1 bear the same reference numerals. Those parts which correspond in construction and function but are difierent in form from the parts shown in Figure 1 bear the same reference numerals plus the index letter y. In this embodiment (Figure 6) the back stop 33 is formed as a part of the gravity actuated lever 20y instead of as a part of the guard as in Figure 1.

parts which are of the same construction as corresponding parts in Figure 1 bear the same reference numerals and those parts which are of similar construction and perform the same function as corresponding arts in Figure 1, but differ therefrom in orm, bear the same reference numerals plus the index character as. In the embodiment of Figure 5 it will be observed that the guard is a single guard and the gravity actuated In the embodiment shown in Figure 5 those v lever has but a single loop 26a; instead of the double guard and loop structure shown in Figure 1.

The electric stop mechanism which is controlled by my circuit closer may be of the ordinary construction, and as it per se forms no part of the present invention, it has been merely diagrammatically indicated in Figure 1, by reference to which it will be observed that 34 is the battery and 35 the magnet which actuates the stop motion -actuating lever 36 to stop the machine when the magnet is energized.

In the use of my invention the device is mounted at a suitable location on the knitting machine and the thread is laid over the two levers 20 and 13 so as to lie in theconcavity of fingers 14 as best shown in Figures 1, 2, 4 and 5 of the drawings.

When the thread is running through the machine it is under suflicient tension to hold the gravity actuated lever in substantially the positions indicated in Figures 1, 4, 5-and 6. The gravity actuated lever being overbalanced by the weight-lever 24, continuously tends to raise the thread so as to reduce its frictional contact area with the fingers 14 tending to assume the position shown in Figure 2 but normally not quite reaching that position. When, however, the thread slacks then the position shown in Figure 2 and in dotted lines in Figure 1 will be reached, but the electric circuit will not be closed in the box 7 because the guard 28 overlies the thread T and prevents the gravity actuated lever from kraising to its circuit closed position. However, as soon as theend of the thread passes the guard the. lever 20 will rise and close the circuit, thus stopping the movement of the knitting machine. Furthermore, if undue tensionis put upon the thread as for movement of the thread before it reaches the circuit closer, the thread will. pull down the levers 20 and 13 and slip off of the same, thereby at once releasing both the levers 13 and 20 and permitting them to close the electric circuit. The arrangement is preferably such that as the lever 13 is pulled down to a position about to release the thread, its heel 16 will make electrical connection with the spring 10 and at once close the circuit to the stop mechanism.

' The back stops 30, 30m and 33 serve to prevent the thread from working back over the ation and advantages of my invention will be clear to those skilled in the art to which it relates.

example if a knot causing a stoppage of the it to a circuit closing position.

What I claim is:

1. In stop mechanism ,under control of a travelling thread, a circuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially parallel arms extend ing to the outside of said housing, and having a contact heel to engage said contact member when said arms are pulled down, a gravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member when said gravity actuated lever is moved upwardly beyond a predetermined I position, said gravity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalanclng means continuously tending to move said gravity actuated lever to bring its fore end above said arms and move In stop mechanism under control of a travelling thread, acircuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially/ parallel arms extending to the outside of said housing, and having a contact heel to engage said contact member when said arms are pulled down, a gravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member when said gravity actuated lever is moved upwardly beyond a predetermined position, said gravity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalancing means continuously tending to move saidgravity actuated lever to bring its fore end above said arms and move it to a circuit closing position, and a guard member mounted on'said housing to hold said gravity actuated lever against closing the circuit so long as a thread lies over the fore end of said lever.

3. In stop mechanism under control of a travelling thread, a circuit closer unit comprising a housing,a fixed contact member insulated from and mounted in said housing,

- a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially parallel arms extending to the outside of said housing, and having a contact heel to engage said contact member when said arms are pulled down, a avity actuated lever also fulcrumed in saifl iouslng and having a contact heel to engage said contact 2 member when said gravity actuated lever is moved upwardly beyond a predetermined position, said gravity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalancing means continuously position, sa1d move it to a circuit closing position, and a vertical back stop located between said arms.

4. In stop mechanism under control of a travelling thread, a circuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially parallel arms extending to the outside of said housing, tact heel to engage said contact member when said arms are pulled down, agravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member when said gravityactuated lever is moved upwardly beyond a predetermined position, said gravity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalancing means continuously tending to move said gravity actuated lever to bring its fore end above said arms and move it to a circuit closing position, and a guard member mounted on said housing to hold said gravity actuated lever a ainst closing the circuit so long as a threa lies over the fore end of said lever, said guard member also including an upright back stop located between said arms.

5. In stop mechanism under control of a travelling thread, a circuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially parallel arms extending to the outside of said housing, and having a contact heel to engage said contact member when said arms are pulled down, a gravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member whensaid gravity actuated lever is moved upwardly beyond a predetermined avity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalancing means continuously tending to move said gravity actuated leverto bring its fore end above said arms and move it to a circuit closing position, said overbalancing means comprising a pivoted member mounted on said housing and a finger on said gravity actuated lever to underlie said pivoted member.

6. In stop mechanism under control of a travelling thread, a circuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminal therefor, a spring-held lever fulcrumed in said housing and including two substantially parallel arms extending to the and having a con-' 5 guard comprising portions to lie betweeneach said arms are pulled down, a gravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member when said gravity actuated lever is moved upwardly beyond a predetermined position, said gravity actuated lever having its fore end positioned to be held between said parallel arms the thread placed thereover,

and overbalancing means continuously tending to move said gravity actuated lever to bring its fore end above said arms and move it to a' circuit closing position, and a guard member including a projection serving as a stop to limit the upward movement of said gravity actuated lever."

7. In stop mechanism under control of' a travelling thread, a circuit closer unit comprising a housing, a fixed contact member insulated from and mounted in said housing, a circuit terminalv therefor, a spring-held lever fulcrumed in said housing andincluding two substantially parallel arms extending to the outside of said housing, and having a contact heel to engage said contact member when said arms are pulled down, a gravity actuated lever also fulcrumed in said housing and having a contact heel to engage said contact member whensaid gravity actuated lever is moved upwardly beyond a predetermined position, said gravity actuated lever having its fore end positioned to be held between said parallel arms by the thread placed thereover, and overbalancing means continuously tending to move said gravity actuated lever to bring its fore end above said arms and move it to a circuit closing position, and a guard member mounted on said housing to hold said gravity actuated lever against closing the circuit so long as a thread lies over the fore end of said lever, said gravity actuated leveihaving its fore part formed with a plurality of parallel portions adapted to be caused to lie between said arms when a thread is in place, and said pair of said plurality of parallel portions, said guard member including a projection serving as a stop to limit the upward movement of said gravity actuated lever.

JACOB WAGHSMAN. 

